This invention relates to a system to mix oil and water to produce an emulsified mixture and deliver it to the burner.
In conventional systems of this kind, as shown in FIG. 1, the oil, water and emulsifier are supplied by the constant flow pumps P1, P2 and P3 to the emulsifying tank T1 where they are mixed by the agitator M to be emulsified, and then the mixture is delivered by the pump P4 to the auxiliary storage tank T2, from which it is sent to the burner B.sub.P having a pump. The excess fuel which was not burned in the burner is returned to the auxiliary tank T2.
The system with the above construction has various drawbacks. The fuel, after being thoroughly mixed for 5 to 10 minutes in the tank T1, is intermittently supplied to the auxiliary tank T2 and therefore it is diffucult to have as much fuel as is necessary for the burner supplied by the pump P4 to the auxiliary tank T2. For this reason, the emulsified fuel staying in the auxiliary tank T2 is liable to become separated into oil and water. Since the system requires two tanks, the emulsifying tank T1 and the auxiliary tank T2, the system is subject to the regulation of fire laws (according to the volume of tanks) for the purpose of preventing fire.
The emulsified fuel in the tank T1 is transferred to the auxiliary tank T2 to stabilize it. However, if the fuel is left in the Tank T2 for more than a certain period of time, the emulsion may become separated into oil and water, bringing bad effects on the combustion. The fuel mixture that has been returned from the burner to the auxiliary tank T2 will also become separated with the lapse of time. This separation can easily occur especially with light oils (A-heavy oil, kerosene, etc.). Furthermore, since the system must be equipped with tanks, it is unavoidable that the size of the system becomes large. In the conventional method, the emulsifier must be added in the emulsifying tank T1, while this invention does not require the emulsifier because the emulsifying time is so short that it is possible to supply the emulsion fuel to the burner before it is separated.
This invention has been accomplished to overcome the aforementioned drawbacks of the conventional system and it will be explained referring to the accompanying drawings.